Lock mechanism

ABSTRACT

A lock incorporating two locking positions and formed by a body with a key plug and cylinder coaxially rotatable therein. Locking pins in the body plug and cylinder adapted to be aligned by one key so as not to transverse the line of junction between the cylinder and key plug and with another key so as not to transverse the line of junction between the cylinder and body of the lock. A further pin within a further hole in the cylinder in one position locks the cylinder and key plug together.

United States Patent [72] Inventor Bessim Bessim 349 Arcand St.,Cap-De-La-Madeleine, Quebec, Canada [21] App]. No. 27,471

[22] Filed Apr. 13, 1970 [45] Patented Aug. 17, 1971 [54] LOCK MECHANISMfF U Q 4 2 765L621? R 1,433,591 10/1922 Abell .1 70/341 1,650,56411/1927 70/364 A 2,596,720 5/1952 70/364 A 3,070,987 l/l963 Baker 70/383Primary Examiner-lan A. Calvert Assistant Examiner-Robert L. WolfeAttorney-Alan Swabey ABSTRACT: A lock incorporating two lockingpositions and formed by a body with a key plug and cylinder coaxiallyrotatable therein. Locking pins in the body plug and cylinder adapted tobe aligned by one key so as not to transverse the line of junctionbetween the cylinder and key plug and with another key so as not totransverse the line of junction between the cylinder and body of thelock. A further pin within a further hole in the cylinder in oneposition locks the cylinder and key plug together.

PAITENTEDAUBHIQYI 3,599,456

Bessim BESSIM ATTORNEY LOCK MECHANISM 1. Field of the Invention Thepresent invention relates to locks. More particularly, the presentinvention relates to locking mechanisms having two separate. anddistinct locking positions requiring two separate and distinct releasingmeans (keys) one of which is operable in both locking positions.

2. Description of Prior Art Pin tumbler locks are used for a multitudeof applications including automobiles, various doors and drawers, etc.Generally, these locks operate on the principle of aligning the ends ofthe pins and tumblers with the line of demarcation between the key plugand tumbler carrier in the housing of the lock to release the key plugfor rotation.

It is sometimes desirable to have two degrees of locking safety for agiven installation, for example, it is sometimes desirable to maintainthe area locked while permitting access by certain people or a specificperson during limited periods of time without permitting complete accessfor this person at any time and without leaving the area unlocked. Nosuitable device for accomplishing this other than the use of twoseparate and distinct locks is presently available.

SUMMARY OF INVENTION It is thus the main object of the present inventionto provide a single lock structure operable by a pair of different keys,one of which is only operable to unlock the lock when it is in one ofthe locking positions.

Broadly, the present invention relates to a lock including a key plugconcentric with and rotatable in an intermediate cylinder which in turnis rotatable in the body of the lock, there being a pair of rows ofindividual pushdown tumblers arranged for movement in cylindrical holesextending substantially radially of the axis of rotation of the plug andintermediate cylinder. A set of key tumblers are positioned in suitableholes in the key plug and intermediate cylinder and are adapted tocooperate with the pushdown tumblers to be biased into a lockingposition preventing relative rotation of the plug, intermediate cylinderand body member. The tumbler pins, being adapted, upon insertion of onekey, have to be aligned to permit relative rotation of the plug andintermediate cylinder while locking the intermediate cylinder and bodyof the lock together and with a second key to have the ends of thetumblers aligned with the line of juncture between the intermediatecylinder and the body of the lock to permit relative movement betweenthe intermediate cylinder and the body of the lock while locking theintermediate cylinder and tumbler together.

BRIEF DESCRIPTION OF DRAWINGS Further features, objects and advantageswill be evident from the following detailed description of a preferredembodiment of the present invention taken in conjunction with theaccompanying drawings in which:

FIG. 1 is a section along the line 1-] of FIG. 2 illustrating one set ofpushdown tumblers and key tumblers together with the key plug andintermediate cylinder of the present invention;

FIG. 2 is a partial section along the line 2-2 of FIG. 1;

FIG. 3 is a front view illustrating the key slot of the presentinvention;

FIG. 3a is a partial section of the key slot with a key being inserted;

FIG. 4 is a view similar to FIG. 1 but showing the effect of thesecondary key on the system;

FIG. 5 is a view similar to FIG. 4 but with the master key in operativeposition;

FIG. 6 is a view along the line 6-6 of FIG. 7 showing the intermediatecylinder and plug aligned with the second locking position of thelocking mechanism and having a secondary key inserted;

FIG. 7 is a partial section along the lline 7-7 of FIG. 6 illustratingthe locking detent in position;

FIG. 8 illustrates a modification of the detent mechanism which preventsrelative rotation between the plug and cylinder and cylinder and body ofmore than 360.

DESCRIPTION OF PREFERRED EMBODIMENTS In the illustrated arrangements,the: throw bar or bars or switches actuated by turning of the keys inthe lock have not been illustrated. Any suitable and/or conventionalconnecting means between the key plug and the element or elements to belocked may be provided.

As shown in the figures, the lock ll) has a main body 12 whichincorporates a pair of tumbler receptacles 141a and Mb (see FIGS. 2 and7). Rotatably mounted in the body portion 12 is an intermediate cylinderI6 and rotatably mounted within and concentric with the cylinder 16 is akey plug 18. The intermediate cylinder 16 and key plug 18 are retainedin the body 12 by means of a retainer end washer 19 which is bolted orotherwise secured to the plug 18, retaining bothinterrnediate cylinderand plug from moving axially apart from body 12. The retainer washer 19may serve yet another function, namely to retain the means connectingthe key plug to a conventional locking mechanism.

Each of the retainers 14a and 14b has a plurality of guide holes whichwill be described first in relation to retainer 14b. As shown in FIG. 1,retainer 14b includes a plurality of guide holes 20, each containing apushdown tumbler pin 22 which is biased toward the intermediate cylinder16 by means of springs 24 trapped within the guide holes 20 by a coverplate 26. The guide holes 20 extend substantially radially of the axesof rotation of the key plug 18 and intermediate cylinder 16. The guideholes and equivalent parts in the retainer Ma for convenience have beenindicated with the same reference numbers as those described above withrespect to retainer 14111 but followed by the letter a (see FIG. 6).

The retainer 14b is provided with one supplemental radial guide hole 20'which in the illustrated] arrangement is posi-- tioned at the rear ofthe lock 10. This guide hole 20' contains a pushdown tumbler pin 22which is biased toward the intermediate cylinder 16 by means of a spring24' that is stronger than the individual springs 24 and 24a describedhereinabove. The intermediate cylinder and the key plug 18 are eachprovided with a plurality of radial guide holes 28 and 30 respectively.Suitable key end tumbler pins 32 and in some cases in the illustratedarrangement key end tumbler pins 32 and intermediate tumbler pins 34 arereceived within the guide holes 28 and 30. The intermediate pins 34 arenot essential but are preferred to permit a maximum variation in keyshapes and easy differentiation in shape between the master key A andsecondary key B as will be more evident from the descriptionhereinbelow. Each guide hole 20 has corresponding guide holes 28 and 30in the intermediate cylinder and key plug and suitable pins 22, 32 and34 are retained within these holes to operate the locking mechanism. Theholes 20, 20a, 28 and 30 are of substantially the same cross-sectionalshape and size and the pins 22, 32 and 34 can slide axially in all theseholes.

The intermediate cylinder 16 is provided with a further radial hole 28'adapted to align with the hole 20' in the retainer 14b. A locking pin ordetent pin 34 is received within the hole 22 and is adapted to projectinto a locking blind hole or pit 36 formed in the key plug 18 (see FIG.4). The pin 34 functions as a detent when the intermediate cylinder 16has its holes 28 in alignment with the holes 20 in the retainer l4lb andas a locking pin to hold the holes 28 and 30 aligned when the holes 28and 20 are not aligned. As will be described in more detail hereinbelow,the pin 34' must be slightly longer than the radial thickness of theintermediate cylinder 116, ie the length of the slot or hole 28'. Thepin 22 is adapted to cooperate with a blind hole or pit 21 in thecylinder 16 to function as a detent pin indicating alignment of thecylinder with the retainer 14a (see FIG. 7).

The key plug 18 has a conventional key slot 38 and is provided with arib 40 or other conventional means to hold the pins 22, 34 and 32 in aposition higher in level than key slope tip 2 (see FIGS. 1, 3 and 3a).

The operation of the lock will now be described with respect to FIGS. 4to 7 inclusive.

Assuming that the lock is in position with the holes 28 and 30 alignedwith the holes 20 in the retainer 14b, i.e. in a position where thesecondary key B is operable, insertion of the key B aligns the ends ofthe tumblers with the junction or line of demarcation 42 between theintermediate cylinder 16 and the key plug 18 with some of the pins 22 or34 traversing the junction line 44 between the cylinder 16 and body 12(see FIG. 4). It will be noted that the tumbler 34' is retained withinthe blind hole or pit 36 and functions as a detent to indicate alignmentof the holes 20, 28 and 30 but does not prevent relative rotation of theplug 18 to the cylinder 16. Thus, with the key 13 in position as shownin FIG. 4, rotation of this key B will turn the key plug 18 since thereare no pins 22, 32 or 34 projecting across the junction line 42 and thedetent pin 34' will simply be forced out of the hole 36 by compressingthe spring 24'. Rotation of the key plug 18 locks or unlocks the bolt orthe like connected with the plug 18 in the conventional manner.

When it is desired to lock the lock so that the key B will beinoperative, the key A must be inserted into the slot 38 as shown inFIG. 5. This aligns the ends of the tumblers with the junction or lineor demarcation 44 between the intermediate cylinder 16 and the body 12(there being no tumbler pins traversing line 44) and permits relativerotation of the intermediate cylinder 16 in the body 12. The key plug 18is locked to and turnswith the cylinder 16 as some of the pins 32 or 34traverse the line of junction 42 and the pin 34' is trapped in the hole28' and blind hole or pit 36. Thus, turning the key A turns both thecylinder 16 and the key plug 18 and thus permits opening of the lock orturning of the lock into alignment with the retainer 14a.

If desired, the key A can rotate the cylinder 16 and plug 18 to theposition shown in FIG. 5 and wherein the holes 28 and 30 are alignedwith the holes a in the receptacle 14a. With the cylinder 16 and plug 18in the position shown in FIG. 6, the secondary key B cannot besubstituted for key A to open the lock 10. As shown in this figure, thekey B aligns the tumblers 22a, 32 or 34 so that none traverse the lineof juncture 42. However, the pin 34' is trapped in the hole 28 and blindhole or pit 36 thereby locking the plug 18 to the cylinder 16 andpreventing relative movement therebetween. Rotation of the cylinder 16and plug 18 together within the body 12 is prevented by pins 22a, etc.,traversing the junction line 44. Thus, in the position shown in FIG. 6with the holes in the key plug 18 and intermediate cylinder 16 alignedwith the holes 20a in the receptacle 14a, operation by secondary key Bis prevented.

From the above, it is apparent that the key A will operate the lock 10regardless of whether the holes in the intermediate cylinder and plugare aligned with the holes in the receptacle 14a or 14b while the key Bcan only operate in the latter position.

FIG. 8 illustrates a modification of the blind holes or pits 21 and 36adapted to limit rotation of the cylinder 16 relative to the body 12 andto less than 360 and relative rotational movement between the plug 18and cylinder 16 to less than 360. As shown, the cylinder 16 and plug 18are provided with looking holes 21a and 21b and 36a and 36b respectivelywith a stop 23 and 37 respectively positioned therebetween to limit therotational movement of the cylinder 16 and key plug 18.

Modifications may be made without departing from the spirit of theinvention as defined in the appended claims.

I claim:

1. A lock including a body having locking positions, an intermediatecylinder rotatably mounted in said body and a key plug rotatab y mountedin said cylinder, said key plug and cylinder being coaxially mounted forrotation about an axes, a plurality of radial holes in said plug andcylinder and in said body in said locking positions, tumbler pins insaid holes, means biasing said tumbler pins towards said plug in saidlocking position, said holes in. said plug being alignable with saidholes in said cylinder and with said holes in said body in each of saidlocking positions, a further radial hole in said cylinder and a blindhole in said plug, a locking pin in said further hole, said locking pinbeing adapted to cooperate with said blind hole in said plug.

2. A lock as defined in claim 1, further comprising a supplemental holein said body in one of said locking positions, said supplemental holecontaining a pin, means biasing said pin towards said cylinder, saidblind hole and said further hole being alignable with said supplementalhole in said one locking position whereby said pin and said locking pincooperate to form a detent biased into said blind hole for aligning saidplug and cylinder in said one position.

3. A lock as defined in claim 2, wherein said locking pin is trapped insaid further hole and said blind hole thereby locking said key plug andcylinder together when said plug and cylinder are simultaneously movedfrom said one position.

4. A lock as defined in claim 3, further comprising a detent hole insaid cylinder, said detent hole being alignable with said pin in saidsupplemental hole in another of said locking positions.

5. A lock as defined in claim 1, wherein said tumbler pins includepushdown pins, intermediate pins and key end pins.

6. A lock as defined in claim 3, wherein said tumbler pins includepushdown pins, intermediate pins and key end pins.

7. A lock as defined in claim 4, wherein said tumbler pins includepushdown pins, intermediate pins and key end pinsv 8. A lock as definedin claim 4, wherein one key is adapted to operate said lock to alignsaid tumbler pins so that none traverse a junction line between saidplug and cylinder, and wherein another key is adapted to operate saidlock to align said tumbler pins so that none of said tumbler pinstraverse a line of junction between said cylinder and body.

9. A lock as defined in claim 7, wherein one key is adapted to operatesaid lock to align said tumbler pins so that none traverse a junctionline between said plug and cylinder, and wherein another key is adaptedto operate said lock to align said tumbler pins so that none of saidtumbler pins traverse a line of junction between said cylinder and body.

10. A lock as defined in claim 9, wherein said holes are arranged inrows in said key plug, said cylinder and said locking positions in saidbody.

1. A lock including a body having locking positions, an intermediatecylinder rotatably mounted in said body and a key plug rotatably mountedin said cylinder, said key plug and cylinder being coaxially mounted forrotation about an axes, a plurality of radial holes in said plug andcylinder and in said body in said locking positions, tumbler pins insaid holes, means biasing said tumbler pins towards said plug in saidlocking position, said holes in said plug being alignable with saidholes in said cylinder and with said holes in said body in each of saidlocking positions, a further radial hole in said cylinder and a blindhole in said plug, a locking pin in said further hole, said locking pinbeing adapted to cooperate with said blind hole in said plug.
 2. A lockas defined in claim 1, further comprising a supplemental hole in saidbody in one of said locking positions, said supplemental hole containinga pin, means biasing said pin towards said cylinder, said blind hole andsaid further hole being alignable with said supplemental hole in saidone locking position whereby said pin and said locking pin cooperate toform a detent biased into said blind hole for aligning said plug andcylinder in said one position.
 3. A lock as defined in claim 2, whereinsaid locking pin is trapped in said further hole and said blind holethereby locking said key plug and cylinder together when said plug andcylinder are simultaneously moved from said one position.
 4. A lock asdefined in claim 3, further comprising a detent hole in said cylinder,said detent hole being alignable with said pin in said supplemental holein another of said locking positions.
 5. A lock as defined in claim 1,wherein said tumbler pins include pushdown pins, intermediate pins andkey end pins.
 6. A lock as defined in claim 3, wherein said tumbler pinsinclude pushdown pins, intermediate pins and key end pins.
 7. A lock asdefined in claim 4, wherein said tumbler pins include pushdown pins,intermediate pins and key end pins.
 8. A lock as defined in claim 4,wherein one key is adapted to operate said lock to align said tumblerpins so that none traverse a junction line between said plug andcylinder, and wherein another key is adapted to operate said lock toalign said tumbler pins so that none of said tumbler pins traverse aline of junction between said cylinder and body.
 9. A lock as defined inclaim 7, wherein one key is adapted to operate said lock to align saidtumbler pins so that none traverse a junction line between said plug andcylinder, and wherein another key is adapted to operate said lock toalign said tumbler pins so that none of said tumbler pins traverse aline of junction between said cylinder and body.
 10. A lock as definedin claim 9, wherein said holes are arranged in rows in said key plug,said cylinder and said locking positions in said body.